Visioning County Food Production - Part Two: General Problem Areas in Sustainable Agricultural Design

In Part One of this series, I noted that providing for the
local food needs of urban populations requires a design that
integrates three overlapping categories of production systems:
urban agriculture systems (many small islands of gardening in the
city center), peri-urban agriculture (larger production areas on
the immediate periphery), and rural agriculture (feeder farms
associated with village-size population clusters in the hinterland
of the city but close enough to be satellite hamlets). In this
month’s article, I will discuss four key issues that must be
addressed in order to envision these three systems: fertility,
energy, water, and pest control. But first, a word about the role
of species diversity in addressing these issues.

In an energy descent environment, agriculture that incorporates
the necessary diversity of species that are multifunctional
— providing both ecological and other services and food
— will gradually replace the current agriculture that
substitutes external inputs to solve these problems.

Some of the most durable and productive low input farming
systems in history are designed around animals that can accelerate
the growth and conversion of plants to fertilizer. Because they
are highly multifunctional, ruminant mammals rank highest among
these. Beyond their manure production function, they can consume
fibrous perennials unusable for human food. These perennials can
grow on hill land too rocky or too erodable for food
cropping. Used as work animals, ruminants multiply the energy
input from human labor many times. They provide a source of
concentrated protein food that can be conserved and stockpiled for
winter consumption. They provide hides and fiber for clothing as
well. Cattle, sheep, goats, alpacas, llamas and bison are
ruminants that we can most easily use in agricultural systems in
our environment.

A few other animals serve some of these functions and, properly
integrated, often are found enhancing these systems. Pigs and
poultry can do the hard labor of turning manure into compost, and
can thrive by consuming unused and pest species as well as waste
streams from farms and kitchens. They both can reduce a patch of
weeds to bare ground ready for planting, and pigs will perform
tillage as well. They will consume crop residues and garbage from
food preparation, and convert it to fertilizer as well as their
own production as food animals. Poultry will consume weeds and
insect pests. Edible fish and other water animals like frogs and
snails can perform the same functions in aquatic systems. This map
of flows among components demonstrates the potential of integrated
systems (Figure 1). Notice that the flows may go in both
directions among all components:

Figure 1. Dynamics of a hypothetical sustainable system

1. Soil Fertility

As energy descent deepens, two key fertility crutches of
industrial agriculture will become cost-prohibitive. Synthetic
nitrogen fertilizer production requires large quantities of
energy. The decreasing quality of phosphate deposits is already
driving up the price of phosphate fertilizer (up 700 percent in a
recent 14-month period) and production is estimated to peak within
20 years.[1] Moreover, the affordability of most off-farm sources
of fertility is derivative of cheap oil. But minerals essential to
farm fertility can be recirculated within farms or at least within
local food systems, and recirculation capacity will become
essential to sustainable design.

On-farm recycling. Building high levels of soil organic
matter (SOM) will be central to agroecosystem design because SOM
is key to achieving not only fertility goals, but also healthy
water and mineral cycles, maximal photosynthetic energy capture
and use, and optimal biodiversity. Humid, temperate environment
soils are exceptional in their ability to store organic
matter. French scientist Andre Voisin demonstrated 50 years ago
that pulsed grazing (explained below) on permanent pasture is the
fastest soil organic matter building tool that farmers have, at
least in temperate climates like ours.[2]

The structural element historically proven to work best in
these environments is a grass/ruminant complex. This subsystem
works on the principle that manure from a portion of the farm
devoted to grazing animals will not only sustain the fertility of
their forage land, but generate a surplus that will sustain a
smaller acreage of annual crops (Figure 2). It can sustain
fertility well enough to have generated numerous historical models
around the world. The process was used in lowland northern Europe
and New England before the industrial age.[3] Cuban research into
its potential demonstrated the effective ratio of forage acreage
to support cropland fertility to be 3:1 in that environment. In
other words, the ruminant stock subsisting on three acres of
forage produced enough manure to sustain both the fertility of the
forage land and one acre of cropland. This conceptual model,
adapted for environmental differences, provides a basis for system
design here. Perhaps the most important design question for our
purposes is the ratio of forage to cropland that is sustainable in
our environment.

Figure 2. Fertility subsystem conceptual model

The full soil organic matter building process requires a design
focus on three crucial areas of the agroecosystem:

Pasture management for a wide variety of productive,
palatable perennial forages, kept in a vegetative state (high
growth) by pulsed grazing (see below) throughout the growing
season to maximize biomass production;

Manure storage in a deep litter bedding pack under cover
during the cold season to maximize nutrient retention and
livestock health;

Conversion of the bedding pack to compost at a proper C/N
ratio during the warm season to maximize organic matter
production, nutrient stabilization, and retention;

Field application of the compost during the warm season as
well, to maximize efficient nutrient recycling to the
soil.

Pulsed grazing is so important to the success of the soil
building subsystem that it warrants an explanation in some
detail. Pulsed grazing is a method of repeated grazing of paddocks
in a pasture that controls stock density and timing of stock
movement in and out of paddocks to maximize forage production over
the growing season. This in turn maximizes manure production to
build soil organic matter. Forage plants experience repeated
pulses of growth and removal of biomass, both above and below
ground, over the growing season. Key points :

Stock enter a paddock before forage leaves its vegetative
stage and growth slows.

Stock leave a paddock while there is still sufficient
forage leaf area to jump-start regrowth.

Stock return to the same paddock when leaf and root
regrowth have fully recovered vigor and abiity to recover from
another grazing.

Recycling from Human Communities. It should be clear
from the integrated model (Figure 1) that solving the fertility
problem must include repairing the broken nutrient cycle between
human excreta and the land. If this seems an insurmountable
challenge to modern urbanites, we need only recall from history
that whole societies including large cities have managed excellent
recycling of “night soil.” Among the numerous examples
is China, where until the 1950s, 98% of the fertilizer used to
grow food came from recycled and organic sources.[4]
Relocalization of food production is necessary to reduce the cost
of repairing the nutrient cycle. If Tompkins County exports milk
products to NYC, what will it cost to return the nutrients in the
exported milk to our farmland? In a more county-based food system,
methods for recycling humanure and other food garbage that are
appropriate to urban, peri-urban, and rural farming sites are more
feasible, and will be discussed in the sections devoted to these
production systems.

2. Energy Capture

Ancient sunlight in fast-depleting, finite sources (oil,
gas, coal) presently supplies over 80% of the energy used in the
industrial form of agriculture that produces most of the food
consumed in the United States. Natural ecosystems consist of food
chains supported entirely by current sunlight, so it is
easy to design farming systems to work the same way, as was done
through most of agricultural history. Solar energy that is
accessible directly on farms comes in forms that are far less
concentrated than the fossil fuels that we are used to. Therefore
we need to design farms that can be productive on far less
energy. The challenge is to capture solar energy in as many places
as possible as it flows through the agroecosystem.

The carbon cycle is an important way solar energy flows through
our world. All metabolic processes in agriculture and other
biological systems release carbon to the atmosphere. Tillage that
stimulates activity in the soil food web, animal and human
digestion and composting are examples. But criticism of these
processes as feeding greenhouse gas build-up is mistaken. Biomass
conversion to food, fertilizer, or fuel is carbon-neutral over
time because its emissions, unlike those of fossil fuels, are part
of the biospheric carbon cycle. The important question here is how
to manage the carbon cycle to maximize long-term levels of soil
carbon sequestered as soil organic matter.

Animal Power. Currently (2009) people tend think of
solar capture in terms of relatively high technologies like those
that convert wind and sunlight to electricity. Working models
exist of homesteads and even farms that are self-sufficient in
electricity using small-scale equipment of this sort. However,
most analyses of economic viability related to wind/solar
electricity production at any scale are based on current costs in
the manufacture and maintenance of these systems, all of which
still rely on cheap oil. These analyses fail to account for
already exponentially rising costs in raw materials and production
of the equipment. All production costs of such technologies will
rise in parallel with sharply increasing energy costs as the
fossil fuel era declines. Like oil, many raw materials used in
these technologies are finite resources already on the downside of
their historical production curve; they will become unaffordable
for many uses in the future. In sum, the window of opportunity
that makes these alternative energy technologies approach economic
viability now may close in the future as costs begin to rise more
sharply. A 10kw wind-electric rig that can power a small farm
costs about $70,000, and is usually economically unfeasible even
today without subsidies. What will it cost after 15 years of
rising manufacturing costs? What will it cost to replace it after
its 20-30 year lifetime?

However, there are ways of powering farm production that are
more reliably sustainable. Just as the same breeze or brook
flowing through a community might be tapped at a number of points
for wind or hydropower to run a mill or pump water, solar energy
can be captured to produce food or fuel by inserting species
appropriately into the farm food chain. Apart from wind and
flowing water, solar energy enters the farm ecosystem via
photosynthesis in green plants, and flows through the system as
one species feeds on another. Large herbivores tap immediately
into this chain by feeding on plants that are too fibrous for food
use. While they may produce food and fertility as previously
described, they will do double duty as work animals in the future,
thus replacing no longer affordable fossil-fueled machine labor.

Fields that grow the forages that support work animals and
other grazing and foraging species will not compete with
cropland. On the contrary, forage fields will provide an essential
ecological service as the permanent cover necessary to sustain
soil health on all sloping land. Present hillside cropland is
always eroding and will be revealed as unsustainable when the
crutch of cheap synthetic fertilizer is no longer available. This
means that land use plans in hill country like ours will need to
include a mosaic of hillside forage land and relatively flat
cropland. Unless terraced, the hillsides will be most erosion-free
and productive when planned to mimic natural tree-dotted savannas,
as hay/pasture that includes fruit and nut orchards, for
example. The trees themselves will be multi-functional, producing
food or forage, improving the cycling of soil nutrients, providing
windbreaks, and shading the grazing animals.[5]

Integrated as described here, draft animals like oxen, mules,
and horses will optimize the health and productivity of the
agroecosystem.

Biofuels. Energy for winter heating and for cooking is
almost as important as food production for survival in these
latitudes. As much as possible of that energy should come directly
from the sun, as in passive solar designs for both heating and
cooking. But rural land use will need to reflect increasing local
dependence on firewood for the rest. Sustainable forest
management and harvest will again become a significant share of
rural agricultural production, but serving local urban and village
communities not faraway paper mills. Forest conservation and
reforestation should start with places that need to be forested
for additional reasons, like ridge tops that protect water
catchments, and hedgerows that serve as shelterbelts and browse
for livestock.

Production of most other biofuels at any significant scale has
been criticized as unsustainable on many counts. One that may
prove sustainable is small-scale biogas generation on farms,
because it extracts methane from some of the farm’s normal manure
production before it continues in the farm’s nutrient cycling
loop, as in Figure 1. Most attempts at biogas generation on US
farms have been large-scale, high-technology projects aimed at
fixing the pollution problem caused by industrial scale dairy
farming. So far, farmer adoption of the expensive and complex
equipment has been poor, despite subsidies. Meanwhile, small scale
biogas generators aimed at producing light and cooking fuel in
Third World peasant communities have proliferated, because they
cost as little as $30.[6] Biogas production requires no separate
biofuel crop that might compete with food production, or
inefficient distillation process. For these reasons biogas
production at an appropriate scale merits consideration as a way
of capturing solar energy as methane fuel for limited use on farms
and perhaps even surrounding communities.

3. Water Capture and Use

We live in a climate that is wet yet subject to droughts during
the growing season. High productivity food production requires a
constant water supply to cover these gaps. Maximizing
productivity in the small areas devoted to urban agriculture is
especially important, because of their high value in a relocalized
food system. Sufficient water falls on urban areas and needs to be
conserved there. Barrels can catch only a fraction of roof runoff,
and will not be enough for the irrigation needs of a successful
urban and peri- urban agriculture. Small water catchment ponds
must become a normal part of both the public and residential urban
landscape. Pavement runoff will need to be directed to the larger
ponds, which might be located in parks and community gardens.

Rural agriculture will need more extensive water capture plans
to hold and use water for farms and whole watersheds. Such a
system should be gravity feed system, in order to avoid the
increasingly high cost of pumping. An example is the keyline plan
that traps some surface water in upper fields and directs the
excess into strategically located irrigation ponds.[7]

Our irrigation needs in New York may be intermittent but still
will require a lot of pipe and other delivery hardware when scaled
up to cover all food production land. Rising costs of current
irrigation delivery systems may become a limiting factor, forcing
the invention of ones that use cheaper materials. This has been
the experience in Cuba, whose year-round agriculture is heavily
dependent on irrigation. Cuba’s artificially triggered
“peak oil” experience has been a bellwether and a
source of lessons for the rest of the world.

Ponds will be needed to serve numerous purposes, as in Figure
1. Basins to process biodigester outflow and other organic liquid
waste can grow algae and duckweed for animal feed, and then feed
the cleansed water into ponds for fish and other aquaculture, as
in Figure 3. They will attract aquatic life including species
useful for garden pest control, and enhance human quality of life
as they beautify places and improve microclimates.

Wetlands abound in New York and are among the most productive
natural ecosystems. Because of their natural potential, they can
be harnessed for highly productive agricultural use yet be managed
to retain much of their natural function. Historical and
contemporary models include wetland systems that fed older
civilizations from the Aztecs to the Incas in Latin America, as
well as many parts of Southeast Asia today. Typically, as in the
Aztecan systems known as chinampas, farmers cut canals through the
wetland and use the soil to create beds raised above the water
level for agricultural use. The canal system is designed to allow
the water control that keeps the raised beds well watered without
being subject to undesirable flooding. Because of the ubiquitous
water, these wetlands are highly productive as both agricultural
and aquacultural systems. They produce so much biomass that they
tend to maintain their own fertility, dredged from the decomposing
detritus in canal bottoms.

One such wetland, adapted from lowland English agriculture,
became the core of a highly sustainable agricultural system that
supported the population of colonial Concord, Massachusetts for
many generations.[8] The Great Meadow that traversed the village
and all other nearby riverine flood plains was a swamp commons
that was first flooded to deposit silt, then partly drained and
reserved for pasture and hay as it dried out during the growing
season. As in parts of Europe, these well-watered riverine meadows
produced enough livestock feed, livestock, and manure to sustain
the fertility of the adjacent dry lands devoted to tillage
agriculture. Figure 4 shows that already by 1650 careful
allocation of land use had taken place on a functional level to
sustain the whole system. Historical models like these suggest
that we will want to regard modified wetlands as an important
agricultural asset in the energy descent era.

Figure 4. Concord, Massachusetts, 1652. From The Great
Meadow: Farmers and the Land in Colonial Concord.

4. Pest Control

From a systems perspective, pest problems are
“structural,” hence best addressed by system design
rather than treatment with pesticides. In this section I will
summarize two main strategies addressed in order of importance: a
focus on the food species themselves, and then the layout of the
physical and biological environment as it affects these food
species.

Much as health care in humans requires preventive medicine, we
must grow healthy plant and animal species as a first step in pest
control. A primary structural problem is the genetic
industrialization of most agricultural plant and animal species,
which was gradually achieved in modern times by breeding processes
that prioritized productivity and short-term profit over other
genetic traits, like hardiness. Moreover, relying on pesticides,
even “natural” ones, to protect these weakened subspecies
inevitably fails over time because pests gradually adapt to
conditions and treatments that become heavy- handed and
routine. An example is parasite resistance in sheep, which has
been neglected and lost. The resulting industrial breeds must be
medicated so often that the parasites are gradually becoming
immune to most medications. To be sustainable, food production
systems will need to return to varieties and breeds that, while
sometimes less productive, have more genetic defenses. By genetic
selection farmers can rebuild hardiness in industrial breeds as
well.

The design of alternative environments uses three general
strategies of pest control: luring or driving them away with trap
or repellent species or physical barriers; creating species and
habitats that attract “beneficials,” species that prey on pests;
and continually altering the environment with crop and animal
rotations that shift them away from pests.

This last strategy points up a characteristic of the natural
world that needs to be taken into account: it is always
evolving. In the long run this means that pest control strategies
can never be permanent, but must always be evolving to stay a step
ahead of pests as the latter adapt to current controls. The
downfall of industrial pest controls is their heavy- handed
strategy of total pest elimination and routine
medication. Ironically this creates the environments most
conducive to genetic evolution in pest organisms toward immunity
from controls.

Recourse to medicinals and other treatments is a strategy of
last resort, indicating a design failure in the production system,
which must be addressed.

Conclusion

From the foregoing it seems clear that life after fossil fuels
will demand much reorganization of food production. To create a
local agriculture that feeds the county, the map of rural and
urban land use will change dramatically. In the countryside,
wetlands and floodplains, hillsides, flatlands, and woodlands will
have specific uses designed to maximize while sustaining the
productivity of whole agroecosystems. Essential rural land use
components might be:

Hillsides in forage land sufficient to support cropland
fertility.

Flatlands in crop rotations.

Wetlands and floodplains development and water management
for high forage or crop production.

Sufficient forest for county firewood and basic
construction needs, managed for maximum regenerative capacity,
which requires fencing out livestock. Woodland regenerative
capacity equaling 1 cord/acre/year is a common rule of
thumb.

Many uses of city land will no longer be economical in the
coming years. Land will need to be converted to food production
and its supporting functions, like composting and water
conservation. Prime candidates for conversion are the commercial
strips now inhabited by national corporate chain stores. Private
and public parking lots, which energy descent writer William
Kunstler sees as soon-to-be-dysfunctional “missing teeth in the
urban fabric,” are another example. During Cuba’s artificially
triggered encounter with “peak oil,” public interest dictated that
a better use of resources was to raze ageing buildings to create
urban garden space, rather than to restore them.

In the integrated system approach described here, the functions
of plants and animals will undergo marked changes. The functions
of many species to facilitate tight nutrient cycling, labor, and
other services that underpin the health of the whole
agroecosystem, will become more important. In the case of some
animals, these functions will become primary, and food production
will become a secondary function, with numbers of animals on farms
directed to their primary functions. The result will be a general
production system model that aims for maximum sustainability,
remains within the carrying capacity of the natural resource base,
and within that framework, feeds the maximum number of people per
acre of land used.

Categories

1 Comments

Joel Gagnon said:

A very apt overview, Karl, with which I almost entirely agree. I am wondering lately whether the shale gas play may alter the scenario meaningfully, though. With natural gas as the primary source of synthetic nitrogen fertilizer, the reduced price of gas may well delay the transition back to organic sources of fertility. It will take time for fossil fuel use to realign to take better advantage of the enhanced gas production and even out prices across competing fuels. On the plus side, this will buy us a bit of time to ease energy descent, but on the downside it may make it difficult to sustain in the short run the investment that has already been made in redeveloping more traditional systems. Farming is marginal enough without that additional burden. Of course, some will benefit from sale of the mineral rights.

Some time in the next 30 years, life will start to become very different from what it is now. By mid-century we will use much less energy; we will live every aspect of our life much closer to home; and we will be much poorer in material terms, because energy and wealth are basically the same thing in an industrial society.

Energy descent — a radical reduction in our use of energy — is certain, but it’s not clear yet which of several factors will cause it to begin. Perhaps we will decide to do the right thing about climate change and reduce our CO2 emissions 80 or 90 percent, which would require changes almost that large in our actual consumption of energy. And there are other ways we might experience a radical reduction in our use of energy; for example, economic collapse, or an expanded war in the middle east. But the factor that makes energy descent a sure thing and sets the theme for this century is "peak oil" — the leveling off of global oil production and then its eventual and inexorable decline.

The timing of the peak is debatable, with forecasts ranging from 2005 (that is, already here) to 2030. But most credible estimates agree with the U.S. Army Corps of Engineers, which concluded in a recent study that "world oil production is at or near its peak," and with the director of research at OPEC, who said recently that "we are at, or near, the production peak of world oil, if not on the downward slope."

After the peak, the growing gap between falling world oil production and ever-increasing global demand will send prices skyward, with economic results that can only be imagined but will certainly include greatly restricted mobility due to the high cost of fuel and much higher prices for most goods, including food. The result will be less disposable income, a life lived closer to home, and a greater reliance on the goods and services that can be provided locally. Since the supply of oil and other fossil fuels is finite, this outcome is guaranteed. The only question is, Shall we plan for what we can see coming, or just let it happen to us?

A group of area citizens, TCLocal, has begun planning now. TCLocal contributors are committed to researching various aspects of energy descent in Tompkins County and writing up a preliminary plan for each aspect based on purely local challenges and resources. This is one such plan.